From 290b1d2141dd86b5fe45ac675620378286440522 Mon Sep 17 00:00:00 2001
From: Paul DeVito <pdevito3@gmail.com>
Date: Sat, 10 Oct 2026 00:14:20 +0300
Subject: [PATCH] fix(operators)!: drop constant lists in case-insensitive in
 and not-in

The case-insensitive string path of InOperator(true) and NotInOperator(true) now reads the list only from a NewArrayExpression, the shape that the parser makes. The case-sensitive path still accepts a ConstantExpression list. Filter strings do not change.

Examples:
  ComparisonOperator.InOperator(true).GetExpression<TestingPerson>(title.Body, Expression.Constant(new List<string> { "LAMB" }), null)
    before: x => ((x.Title != null) AndAlso <list>.Contains(x.Title.ToLower())), with the list ["lamb"]
    after:  NullReferenceException
  Title ^^* ["LAMB"]
    before and after: matches the title "lamb"

BREAKING CHANGE: a direct call to InOperator(true) or NotInOperator(true) with a ConstantExpression list throws NullReferenceException. Pass Expression.NewArrayInit(typeof(string), ...) instead, or use a filter string.
---
 .../FilterParsingRegressionTests.cs           | 20 -------------------
 QueryKit/Operators/ComparisonOperator.cs      |  6 ++----
 2 files changed, 2 insertions(+), 24 deletions(-)

diff --git a/QueryKit.UnitTests/FilterParsingRegressionTests.cs b/QueryKit.UnitTests/FilterParsingRegressionTests.cs
index d6c67b3..ffd4f0b 100644
--- a/QueryKit.UnitTests/FilterParsingRegressionTests.cs
+++ b/QueryKit.UnitTests/FilterParsingRegressionTests.cs
@@ -261,26 +261,6 @@ public void comparison_operator_factory_has_one_test_case_per_operator_type()
         ComparisonOperatorFactories().Should().HaveCount(24);
     }
 
-    [Theory]
-    [InlineData(false, new[] { "lamb" })]
-    [InlineData(true, new[] { "null", "other" })]
-    public void case_insensitive_in_operator_factory_reads_a_constant_list(bool notIn, string[] expectedFirstNames)
-    {
-        var people = new[]
-        {
-            new TestingPerson { Title = null, FirstName = "null" },
-            new TestingPerson { Title = "Lamb", FirstName = "lamb" },
-            new TestingPerson { Title = "other", FirstName = "other" },
-        };
-        Expression<Func<TestingPerson, string?>> title = x => x.Title;
-        var comparisonOperator = notIn ? ComparisonOperator.NotInOperator(true) : ComparisonOperator.InOperator(true);
-
-        var body = comparisonOperator.GetExpression<TestingPerson>(title.Body, Expression.Constant(new List<string> { "LAMB" }), null);
-        var filterExpression = Expression.Lambda<Func<TestingPerson, bool>>(body, title.Parameters);
-
-        people.AsQueryable().Where(filterExpression).Select(x => x.FirstName).Should().Equal(expectedFirstNames);
-    }
-
     [Fact]
     public void comparison_operator_factory_with_uses_all_builds_all_expression()
     {
diff --git a/QueryKit/Operators/ComparisonOperator.cs b/QueryKit/Operators/ComparisonOperator.cs
index ad8e760..2e01b40 100644
--- a/QueryKit/Operators/ComparisonOperator.cs
+++ b/QueryKit/Operators/ComparisonOperator.cs
@@ -618,8 +618,7 @@ public override Expression GetExpression<T>(Expression left, Expression right, T
                 var listType = typeof(List<string>);
                 var caseList = Activator.CreateInstance(listType);
 
-                // A caller can pass the list as a constant, like v1.14.2.
-                var originalList = (values ?? ((ConstantExpression)right).Value) as IEnumerable<string>;
+                var originalList = values as IEnumerable<string>;
                 foreach (var value in originalList!)
                 {
                     listType.GetMethod("Add")!.Invoke(caseList, new[] { caseMode == CaseInsensitiveMode.Upper ? value.ToUpper() : value.ToLower() });
@@ -864,8 +863,7 @@ public override Expression GetExpression<T>(Expression left, Expression right, T
                 var listType = typeof(List<string>);
                 var caseList = Activator.CreateInstance(listType);
 
-                // A caller can pass the list as a constant, like v1.14.2.
-                var originalList = (values ?? ((ConstantExpression)right).Value) as IEnumerable<string>;
+                var originalList = values as IEnumerable<string>;
                 foreach (var value in originalList!)
                 {
                     listType.GetMethod("Add")!.Invoke(caseList, new[] { caseMode == CaseInsensitiveMode.Upper ? value.ToUpper() : value.ToLower() });